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POIs J2ME's Integer.parseInt() broken?
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copied!<p>While writing a game for J2ME we ran into an issue using java.lang.Integer.parseInt()</p> <p>We have several constant values defined as hex values, for example:</p> <pre><code>CHARACTER_RED = 0xFFAAA005; </code></pre> <p>During the game the value is serialized and is received through a network connection, coming in as a string representation of the hex value. In order to parse it back to an int we unsuccesfully tried the following:</p> <pre><code>// Response contains the value "ffAAA005" for "characterId" string hexValue = response.get("characterId"); // The following throws a NumberFormatException int value = Integer.parseInt(hexValue, 16); </code></pre> <p>Then I ran some tests and tried this:</p> <pre><code>string hexValue = Integer.toHexString(0xFFAAA005); // The following throws a NumberFormatException int value = Integer.parseInt(hexValue, 16); </code></pre> <p>This is the exception from the actual code:</p> <pre><code>java.lang.NumberFormatException: ffaaa005 at java.lang.Integer.parseInt(Integer.java:462) at net.triadgames.acertijo.GameMIDlet.startMIDlet(GameMIDlet.java:109) </code></pre> <p>This I must admit, baffled me. Looking at the parseInt code the NumberFormatException seems to be thrown when the number being parsed "crosses" the "negative/positive boundary" (perhaps someone can edit in the right jargon for this?).</p> <p>Is this the expected behavior for the Integer.parseInt function? In the end I had to write my own hex string parsing function, and I was quite displeased with the provided implementation. </p> <p>In other words, was my expectation of having Integer.parseInt() work on the hex string representation of an integer misguided?</p> <p>EDIT: In my initial posting I wrote 0xFFFAAA005 instead of 0xFFAAA005. I've since corrected that mistake.</p>

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